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contracts...StorageFactory.sol

//SPDX-License-Identifier: MIT
pragma solidity ^0.8.1;

import "./SimpleStorage.sol";

// This is a contract that will let you create and deploy SimpleStorage contracts
// A Contract that creates other contracts - Contract Factory

// In the end, we also inherited SimpleStorage here so that 
// SimpleStorageFactory gets all functionalities of SimpleStorage
contract StorageFactory is SimpleStorage{

    SimpleStorage[] public simpleStorageArray;
    
    function createSimpleStorageContract() public {
        SimpleStorage simpleStorage = new SimpleStorage();
        simpleStorageArray.push( simpleStorage );
    }

    // Store something to simple Storage contract that is deployed using above function
    function sfStore(uint256 _simpleStorageIndex, uint256 _simpleStorageNumber) public{
        // Address of SimpleStorage contract instance

        // ABI - Application Binary Interface
        // Get the simple storage contract ABI that we need to interact using the address
        SimpleStorage( address( simpleStorageArray[ _simpleStorageIndex ] ) ).store( _simpleStorageNumber );
    }

    function sfGet( uint256 _simpleStorageIndex ) public view returns( uint256 ) {
        return SimpleStorage( address( simpleStorageArray[ _simpleStorageIndex ] ) ).retrieve();
    }

}